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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

1966 6 cyl stalls going uphill

  • Thread starter Thread starter Tuffy
  • Start date Start date Apr 26, 2018
T

Tuffy

New Member
Apr 26, 2018
6
0
1
Washington
Apr 26, 2018
#1
  • Apr 26, 2018
  • #1
1966 6 cyl idles perfect, runs perfect on flat road, but stalls horribly going up the slightest hill, replaced the fuel pump and fuel filter, and the problem got a little worse !! Any ideas
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Apr 28, 2018
#2
  • Apr 28, 2018
  • #2
Little background would help, is this your daily driver, did you just get it, did you just do some work to it, does it happen with a full tank? What do you mean by stalls, dies completely? Does it skip for a bit before it dies? Then what happens?
 
T

Tuffy

New Member
Apr 26, 2018
6
0
1
Washington
Apr 28, 2018
#3
  • Apr 28, 2018
  • #3
Thanks for replying I drive it about once a month. I believe I have isolated the problem to what appears to be an external brass check valve between the fuel filter and the carburetor. Having a hard time finding it anywhere to replace it.
 
T

Tuffy

New Member
Apr 26, 2018
6
0
1
Washington
Apr 28, 2018
#4
  • Apr 28, 2018
  • #4
Attached photos
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Apr 28, 2018
#5
  • Apr 28, 2018
  • #5
I don't remember those, from what I remember that type of filter screwed directly into the carb. I wonder what it's purpose was? Can you take the guts out of it and just use it as a fitting? Unless it's a pressure regulator ? I'd gut it and see how it runs.
 
T

Tuffy

New Member
Apr 26, 2018
6
0
1
Washington
Apr 29, 2018
#6
  • Apr 29, 2018
  • #6
I bypassed it .... bad idea it works as a flow regulator and check valve ... I am thinking I may have to buy a new carb that works without that thing
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Apr 29, 2018
#7
  • Apr 29, 2018
  • #7
you can get an adjustable, in line fuel pressure regulator at most auto parts stores.
 
T

Tuffy

New Member
Apr 26, 2018
6
0
1
Washington
Apr 30, 2018
#8
  • Apr 30, 2018
  • #8
Good advice thanks
 
T

Tuffy

New Member
Apr 26, 2018
6
0
1
Washington
May 15, 2018
#9
  • May 15, 2018
  • #9
well i discovered the problem it is a Holley 1940.1 carb not the original . apparently it was common practice for dealerships service sept to replace the entire carb when they came in with issues and this was the go replacement carb. i am going to install the rebuild kit this weekend
 
C

Charlie Cheap

Member
Jun 5, 2018
93
13
18
Abilene, Texas
Jun 5, 2018
#10
  • Jun 5, 2018
  • #10
The 6 cyl. in a Mustang uses a ported vacuum distributor that MUST be matched to the carb. The 1100 one barrel has a control valve on the side of the carb and the distributor has exposed springs if the cap is removed. The dist. must use ported vacuum, not manifold vacuum, to advance the distributor. Going up hill manifold vacuum drops while ported increases, which could explain your problem. Also, in hot weather, the fuel line gets hot causing percolation...not vapor-lock as many think. With the carb mounted over the exhaust and the fuel line running in front of the engine along the head, fuel wants to percolate out of the fuel bowl like an old coffee pot. Insulating the fuel line and/or adding a heat barrier spacer under the carb can help.
 
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